Hey, maybe you forgot your credentials (on your source host or in your ss5.conf) to authenticate between the socks client and the ss5 server. On the other hand, you can check your acls lines in the ss5.conf ---> the 'ISERROR' problem can be linked to this bad configuration: auth 0.0.0.0/0 - - and permit u 0.0.0.0/0 - 0.0. 0.0/0 - - - - - otherwise maybe your ss5.passwd is empty?